This invention relates to a loader, such as a skid steer loader or a multi-terrain loader, and, more particularly, to a control arrangement for such a loader. Loaders of various types are well known in the art, and typically have a body and ground engaging drive elements supporting the body. The drive elements may be either front and rear pairs of driven wheels, or left and driven right endless tracks. Typically, such a loader has left and right interconnected lift arm assemblies that are pivotally mounted to respective tower portions of the body near the rear of the loader, and an implement, such as for example, a bucket, that is pivotally attached at the forward ends of the lift arms. Hydraulic lift actuators or the like are connected between the body and the lift arm assemblies to raise and lower the lift arms. One or more hydraulic actuators are also connected between the lift arm assemblies and the implement to tilt the implement relative to the lift arms during operation of the loader.
Loaders of this type have a great many uses, and they typically have a wide variety of implements that can be readily interchanged. Examples of such implements include dirt buckets, utility buckets, multi-purpose buckets, pallet forks, utility grapple buckets, light material buckets, utility forks, industrial grapple buckets, industrial grapple forks, angle blades, augers, brooms, cold planers, hydraulic hammers, landscape rakes, landscape tillers, material handling arms, stump grinders, trenchers, and vibratory compactors. Dirt buckets and other implements may be used for excavating material, and also for grading, both in a forward direction and in a reverse direction by back blading. Traditional guidance and automated blade control systems of the type used with graders and bulldozers typically include position sensors directly mounted on the machine blades. This is not practical with a loader because of the wide range of movement of the implements, and because of the typical frequent changing of the implements on the loader.
Nevertheless, it is highly desirable to be able to provide control for a loader implement, either by displaying for the operator the position of the implement with respect to the desired height of the implement, or by automated control of the implement.